Final answer:
To determine the magnitude of the average force exerted on the ball by the floor, calculate the ball's change in momentum during the collision and divide by the contact time. The conservation of energy will be used to find the velocities before and after the bounce. The force's direction is upward as it opposes the ball's initial motion.
Step-by-step explanation:
The question pertains to impulse and the average force exerted during a collision. The problem involves a 75-g ball dropped from a certain height and includes details like the contact time with the ground. To find the average force, we first need to calculate the change in momentum of the ball due to the collision, which is equivalent to the impulse imparted to it.
Using the conservation of energy principle, the initial and final speeds just before and after the bounce can be found. Potential energy at the drop height will be converted to kinetic energy just before the collision, and kinetic energy after the collision converts back to potential energy at the rebound height. This allows us to find the velocities at both instances.
Since Impulse = Change in Momentum = Average Force * Contact Time, we can determine the average force by dividing the change in momentum by the time interval, which is given by the ball's contact time with the ground. The direction of the force will be upwards as the ground pushes against the ball.